Branch-chain alkyl derivatives of beta-naphthol



Patented Mar. 16, 1937 BRANCH-CHAIN ALKYL DERIVATIVES F p-NAPHTHOL George W. Itaiziss and Le Roy W. Clemence,

Philadelphia, Pa., assignors to Abbott Laboratories, North Chicago, 111.,

Illinois a corporation of N0 Drawing. Application January 28, 1935,

Serial No. 3,808

I Claims. (Cl. 260-154;)

Our invention relates to a group of compounds which we have prepared and, so far as we know, have not previously been produced, which compounds we find are of high value as bactericidal 5 and bacteriostatic agents. Said compounds are "particularly strong in germicidal effect towards Staphylococcus aureus, which property is of importance in the treatment of infectious diseases. These compounds, furthermore, are of comparatively low toxicity and are, therefore, suitable for general purposes of disinfection.

The compounds which we have prepared and which we consider new may be classed asalkyl derivatives of p-naphthol, wherein the alkyl chain is branched and contains 4, 5, and 6 carbon atoms.

The various alkyl naphthols which we have prepared and investigated and which are listed below may all be prepared by the type method,

hereinafter described, and have all been found to have the highly advantageous properties above referred to. i

The various compounds are all viscous oils, colorless to pale yellow, insoluble in water, soluble in organic solvents, and generally soluble in dilute alkali, with exceptions as noted below.

The following is illustrative of the method used in preparing these substances:

(l-ethyl-propyl-p-naphthol -CH.CH2. CH3

CzHt 110 cc. of per cent sodium hydroxide and allowed to stand for several hours until the layers separate clearly. The insoluble oil is separated; and the alkaline solution washed several times with petroleum ether. The clear alkaline extract is then acidified with hydrochloric acid. The oil which separates is extracted with ether and dried over anhydrous sodium sulfate. After 8 hours it is filtered from the sulfate, the ether distilled off and the resulting oil fractionally distilled in vacuum. Fraction A (unchanged B-naphtho1)-B. P. at 7 mm., distills as an oil, solidifies. M. P. 121". 5

Fraction B, (l-ethyl-propyl) --naphtholB. P. I'll-176 at 6 mm. A light yellowish viscous oil, insoluble in water, soluble in organic solvents, soluble in dilute alkali. 4

This method may also be used in the prepara- 10 tion of alkyl derivatives of a-naphthol wherein the alkyl group contains 4, 5 or 6 carbon atoms, as set forth in our copending application, Serial No. 3,809, filed January 28, 1935.

The Various other compounds listed below may 15 be made by substantially the same procedure, substituting the appropriate alcohol.

B. P Pressure 20 Butyl derivatives lso-butyl fl-naphthol -l90 6mm. Soluble.

(M. F. 80) Secondary-butyl fi-naphthoL. 174-190 6 m n. Do.

Amy! derivatives 5 Isoamylfi-naphthol 17 51 80 5 mm. Do. (l-ethyl-propyl)-fi-naphthol. 17ll76 6 mm. Do (l-methyl-butyl) -fl-naphthol 183-l95 6 mm. D o (Z-methyl-butyD-fl naphthol 209-220 12 mm. Do Tertiary-amyl B-naphth0l 185-190 7 mm. Do.

(M.P.9596) 30 Hezyl derivatives (Methy1-amyl)-fi-naphthol 200-215 7 mm. Do (Ethyl-butyl) -fi-naphthol. l86-1989 7 mm. Do

We clalm as our invention: 5

1. An alkyl derivative of p-naphthol, wherein the alkyl group is branched and contains from 5 to 6 carbon atoms, said derivative having high germicidal effects combined with low toxicity.

2. A compound having the formula- 40 

